1. Field of the Invention
The present invention relates to a suede fabric, and especially, relates to a suede woven fabric which is prepared using a woven fabric as a base sheet material.
2. Description of the Prior Art
Hitherto, there has been a general trend to produce a suede fabric whose sheet material is composed of non-woven fabric and rarely is there seen a suede fabric whose base sheet material is composed of woven fabric as in the present invention. Here, it should be pointed out that the base sheet material of the present invention is not composed of knitted fabric. References which disclose a suede fabric which is composed of woven fabric include the British Pat. No. 1,300,268 (this corresponds also to the Canadian Pat. No. 895,611, the West German Pat. No. 2,035,669, the French Pat. No. 2,059,828 and the Netherlands Pat. No. 7,008,329). The British patent claims in claim 1 in the following way. "A pile sheet material comprising a base sheet and a synthetic polymeric superfine fiber pile formed on at least one surface of said base sheet, the pile fibers having a thickness in denier not exceeding 0.5 and a length (in mm) to thickness ratio falling within the range 0.4 to 5000 and being associated in bundles of at least five such superfine fibers." The characteristics of the suede fabric disclosed by the British patent are (a) the pile fibers having the ratio of length (in mm) to thickness (in denier) falling within the range from 0.4 to 5000 and (b) the pile fibers being associated into bundles of at least five superfine fibers. As is clearly understood from FIG. 7 and FIG. 9 of the patent, the condition (b), which is believed to be more important than the condition (a) in the cited British patent, demands the piles of the suede fabric disclosed by the patent to never exist as individual superfine fibers but to exist as bundles of at least five such superfine fibers. This is an essential requirement for the cited British patent to practice the invention using superfine fibers as a raised material. Moreover, the "islands-in-a-sea" type composite fiber which can be used as the raised material in the British patent is disclosed to be prepared using a melt spinning apparatus for molten polymer as shown in FIG. 3 of the patent. Examples of embodiments of composite fibers prepared, using the spinning apparatus, are shown in FIG. 1 and FIG. 2, wherein No. 1 in the figures is called the sea component and No. 2 is called the island component. The island component No. 2 is nothing but the pile fiber and the sea component No. 1 is removed before the raising. As is apparent from FIG. 1 to FIG. 3, the thickness of each island is substantially the same and adjusted to have such a value as not exceeding 0.5 denier. Moreover, in the specification of the British patent, some examples which are very similar to the present invention are disclosed, namely, Example 7 to Example 9. In these examples, at first, a woven fabric for the suede woven fabric is prepared by using a composite fiber as a weft yarn, but not by interlocking pile fibers into a base sheet material of woven fabric separately. Then, a portion of the composite fiber is raised to form pile fibers using a card wire raising machine. However, in those examples, the composite fiber is used as a spun yarn obtained from short fibers (staple fibers) prepared by cutting the composite fiber, but never is used as a filament alone.
The characteristics of the British Pat. No. 1,300,268 are just as mentioned above. Here, the main difference in the structure of suede fabric of the present invention from the said prior patent can be summarized by three points. (a) Although the composite filament of the present invention (multi-islands randomly distributed in the composite filament) also includes multi-islands in the filament similar to that of the prior patent, the mean thicknesses of those islands in denier are different from each other within the range from 0.05 to 0.50 and, accordingly, they are not substantially the same as those of the prior patent. Moreover, against the uniform distribution of islands in the sea in the prior patent, the distribution of islands in the present invention is random. (b) The multi-islands randomly distributed in the composite filament, which is used as a weft yarn for preparing a woven fabric as a base sheet material for suede fabric, is not used as a set of staple fibers as in the prior patent but is used as filament of themselves. (c) Against the fact that each pile of suede fabric in the prior patent exists as a bundle of at least five superfine island fibers, each pile of suede fabric in the present invention does exist individually as an island monofilament whose mean thickness is in the range of 0.05 to 0.50 denier as mentioned above. The characteristic features of the present invention mentioned above make it possible to achieve superior properties in the product of the present invention which are much better than those of the product of the prior patent.